Acne Vulgaris

This is a disorder of the pilosebaceous follicles found in the face and upper trunk. The primary lesion is the "blackhead" which is a follicle impacted and distended by incompletely desquamated keratinocytes and sebum. Comedones are seen as small white nodules below the skin surface. At puberty, androgens increase the production of sebum from enlarged sebaceous glands that become blocked and infected with Propionibacterium acnes causing an inflammatory reaction. Acne can cause serious psychological problems.

Almost every teenager can expect to experience acne to some degree during the adolescent years. They tend to "grow out of it" by the early 20s but it can persist rather longer. Being mediated by androgens, it tends to affect boys more than girls although the fact that it affects both helps to illustrate that both sexes have both androgens and oestrogens. It is the ratio that differs. Acne tends to occur in adolescence, when hormones are in a state of flux. In girls it may flare up when they are pre-menstrual. The severity of the problem is probably less related to androgen levels as to end-organ sensitivity.

For those who seek a teleological explanation, it remains a conundrum why a condition that so undermines self assurance and self esteem should strike at such a vulnerable time in life.

The appearance of acne vulgaris is well known, usually from personal experience to some degree. The essential features are comedomes or blackheads. They present at the time of puberty and continue for a variable number of years thereafter, usually stopping in late teens or early 20s but uncommonly continuing well into adulthood. They may extend beyond the face to the shoulders, back and even chest. They tend to run a variable course with marked fluctuations, often being worse in girls who are pre-menstrual.

The severity of the condition varies enormously between individuals. It is unsightly but the degree of distress does tend to be disproportionate.

There are 4 types of acne:

• Comedonal acne is the mildest form, without inflammation.
• Inflammatory acne has mild papulopustular acne.
• Scarring papulopustular acne.
• Nodular or scarring acne.

The severest form of acne is called acne conglobata and is discussed elsewhere.

The diagnosis is usually clear and is simply teenage acne but there are aspects that may lead to a question of the diagnosis, especially if it presents at an unusual age.

• Acne can be associated with some of the halogens, especially bromide and iodide. There may be a history of industrial exposure. When associated with halogens or drugs it tends to affect the chest and back rather than the face and comedomes are often absent.
• Rosacea, sometimes called acne rosacea tends to present around middle age or later in life.
• Acne may be a feature of abuse of anabolic steroids.
• Acne may result from abnormal production of androgens. This may occur in Cushing's disease or in virilising tumours in women such as arrhenoblastoma.
• Oestrogens tend to be protective whilst progestogens tend to aggravate acne. This is not usually a problem with the progestogen only pill as the dose of progestogen is so low and the same applies to depot and implant contraceptives. The problem is usually with the low oestrogen, high progestogen combined oral contraceptives.
• Testosterone replacement therapy may induce acne.
• Severe acne or acne conglobata is a serious disease in that it is disfiguring and has enormous psychological impact, and it demands referral to a dermatologist.

Usually no investigations are required. In unusual cases a hormone profile may be useful, including testosterone and SHBG levels.

Non-drug

• Usually acne is a mild and self-limiting condition but teenagers are very sensitive about it and if they have chosen to consult, then it is obviously a matter of concern for the individual. Hence it is important to give the impression that it is being taken seriously and not being dismissed as irrelevant trivia. It is still worthwhile explaining that it is a normal part of adolescence. Everyone gets it and it will go with time.
• Dispel misconceptions about acne being due to poor hygiene or diet. The black tip of a "blackhead" is not dirt and scrubbing may make it worse. Explain that treatment will take several weeks to show an effect. Keep the face clean, washing twice a day with soap and water but a more fastidious regimen may be counterproductive. Proprietary antiseptic products for acne may be beneficial.
• Sunlight or artificial ultraviolet light can be beneficial, especially for those lesions off the face. The usual warnings about sunburn should be given. Superficial x-rays, called Grenz rays used to be used in the 1950s but are no longer employed because of the risk of subsequent skin cancer. PUVA does not appear to be recommended and there are a few case reports of PUVA aggravating the condition.
• Views on diet have been conflicting but more recent evidence suggests possible importance.¹ However, a systematic review was unconvinced about the value of diet, hygiene, face washing and sunlight.² The quality of the evidence is poor.
• Microdermabrasion is a simple outpatient procedure in which aluminum oxide crystals or other abrasive substances are blown onto the face and then vacuumed off, using a single handpiece. It is used for a variety of cosmetic procedures, including the improvement of photoaging, hyperpigmentation, acne, scars and stretch marks. Despite its widespread use, little is known about its mechanism of action but it does seem to be simple, safe and effective.³
• There is interest in laser and light sources as treatment for acne. They tend to be reserved for more severe cases.⁴
• Many men who suffer significant acne into adult life choose to grow a beard to hide it.

Drugs

Topical preparations

• Topical treatments need to be applied to all affected areas and not just to existing lesions. They are only effective on the face and if acne is on other parts, systemic treatment is required.
• Local treatment with tretinoin or adapalene reduces comedones by helping cells lining follicles to slough off. Avoid exposure to strong sunlight. It causes irritation that is greatest after a few weeks. This can be treated with moisturisers.
• Salicylic acid 10% is similar in action to retinoids.
• Azelaic acid is least irritating but it can have a side effect of hypopigmentation.
• For mild papulopustular acne, benzoyl peroxide reduces sebum production and comedones and inhibits the growth of P. acne. It is mildly irritant and causes peeling after a few days. Start with 5% used sparingly, increase usage and/or concentration to 10% later. It tends to produce a burning sensation on the skin after application, especially if it is greasy. It can be combined with topical clindamycin or erythromycin in gel preparations. It is worth pointing out that it is a bleaching agent and so the face should be washed with the hands, not using a flannel and after rinsing thoroughly, it should be dried on a white towel. Use of a coloured flannel or towel will cause bleaching of the material.

Systemic Treatments

• Systemic treatment may be combined with topical treatment.
• Oxytetracycline is first line at 250mg bd. Erythromycin or clindamycin may also be used. The tetracyclines are very interesting because they have not only antibiotic but anti-inflammatory effects.⁵ Minocycline is no more effective than oxytetracycline but it is significantly more expensive. Topical benzoyl peroxide and benzoyl peroxide/erythromycin combinations are similar in efficacy to oral oxytetracycline and minocycline and are not affected by propionibacterial antibiotic resistance.⁶
• Hormonal treatment is applicable only to girls. A predominantly oestrogenic oral contraceptive will help.⁷
• A combination of 50μg of ethinyl oestradiol with the anti-androgen cyproterone used to be available as Dianne™ but now a lower dose called Dianette™ is the preparation that replaces it. It is known generically as co-cyprindol and contains 35μg of ethinyl oestradiol and 2mg cyproterone in each tablet. They are taken 1 daily for 21 days with a break of 7 days for menstruation, exactly the same as the combined oral contraceptives. It is an effective contraceptive but is not licenced as such and the patient must be told. The problem is that if she does get pregnant whilst taking it, any male fetus may suffer feminization as a result of the anti-androgen. The BNF states that "It is no more effective than an oral broad-spectrum antibacterial but is useful in women who also wish to receive oral contraception". Many would disagree and argue that it is rather more effective than antibiotics. It is the most effective hormonal intervention.⁸ Topical cyproterone in an alcoholic lotion is effective but is still used only for girls.⁹ A commercial preparation is not yet available.
• Combining an oral contraceptive or Dianette™ with a tetracycline increases its efficacy but reduces contraceptive effectiveness, perhaps for just the first month and additional precautions are advised. After that they are unnecessary.
• For severe acne, oral isotretinoin is highly effective but toxicity problems confine its use to hospitals under consultant supervision. Dry skin, lips and eyes are common. Raised serum lipids occur in a third of patients. Muscle aches and pains on strenuous exercise, hair thinning and acne flare-up also occur. The main problem is teratogenicity that continues to damage the fetus after discontinuation. Effective contraception is essential in female patients, continued for one month after stopping treatment. Isotretinoin has had some causes for concern in that it has been associated with a variety of adverse psychiatric effects, including depression, psychosis, mood swings, violent behaviour, suicide, and suicide attempts. A review of the evidence¹⁰ concluded that, "Although a variety of anecdotal and epidemiologic studies are available, the overall lack of concrete scientific data limits any conclusion that can be drawn about a causal relationship between istotretinoin and psychiatric adverse events."

Because it is a common, usually self-limiting and non-fatal condition it is very easy to underestimate the destructive effect of acne vulgaris to teenagers. It causes a significant psychological and social morbidity that may be equivalent to that of asthma or epilepsy. Anxiety and depression and a reduction in social functioning are a consequence of this condition.¹¹

This is why it needs to be taken seriously, even if reassurance and some advice is all that is required. If it is more serious it can be very disfiguring. The more severe aspects are considered in the article on acne conglobata. It can have an adverse effect on self-confidence and achievement.

Most cases clear up spontaneously by age 20 but some continue into adulthood.